[LEDE-DEV] [RFC] ipq806x: Add USB Type Selector for R7500

[Mathias Kresin]

2017-02-27 13:34 GMT+01:00 Thomas Reifferscheid <thomas at reifferscheid.org>:
> The patch enables the primary USB port on R7500. Because of the
> missing general IPQ8064x TCSR initialisation functions a workaround
> using pinctrl,single was chosen. It allows us to set 1a4000b0 from
> 0000.0010 to 0000.0011 thus enabling the primary USB port - prior
> to the dwc3-phy initialisation. Needs to be reworked once Qualcomm
> adds TCSR initialisation functionality from their 3.x kernel into 4.x
> kernels.
>
> The patch fixes FS#497 and partially backs off
> 45bf3d4f248ea2d770a1625fdee8899dc40329af which had the right idea but
> was missing the syscon-tcsr handler - which by the time of the upstream
> patch attempt (January 2015) was trying to set the TCSR USB Type
> selector at the wrong part of the kernel.
>
> Signed-off-by: Thomas Reifferscheid <thomas at reifferscheid.org>
> ---
>  ...ipq806x-add-usbtypesel-required-for-r7500.patch | 56 ++++++++++++++++++++++
>  1 file changed, 56 insertions(+)
>  create mode 100644 target/linux/ipq806x/patches-4.4/716-ipq806x-add-usbtypesel-required-for-r7500.patch
>
> diff --git a/target/linux/ipq806x/patches-4.4/716-ipq806x-add-usbtypesel-required-for-r7500.patch b/target/linux/ipq806x/patches-4.4/716-ipq806x-add-usbtypesel-required-for-r7500.patch
> new file mode 100644
> index 0000000..4927708
> --- /dev/null
> +++ b/target/linux/ipq806x/patches-4.4/716-ipq806x-add-usbtypesel-required-for-r7500.patch
> @@ -0,0 +1,56 @@
> +diff -Naur a/arch/arm/boot/dts/qcom-ipq8064.dtsi b/arch/arm/boot/dts/qcom-ipq8064.dtsi
> +--- a/arch/arm/boot/dts/qcom-ipq8064.dtsi      2017-02-27 12:34:58.669161969 +0100
> ++++ b/arch/arm/boot/dts/qcom-ipq8064.dtsi      2017-02-27 12:40:51.253172676 +0100
> +@@ -626,6 +626,13 @@
> +                       reg = <0x1a400000 0x100>;
> +               };
> +
> ++                usbtypesel: pinmux at 1a4000b0 {
> ++                        compatible = "pinctrl-single";
> ++                        pinctrl-single,register-width = <32>;   /* u32                          */
> ++                        pinctrl-single,function-mask = <0x03>;  /* only allow to set the 2 LSBs */
> ++                        reg = <0x1a4000b0 0x04>;                /* u32                          */
> ++                };
> ++
> +               lcc: clock-controller at 28000000 {
> +                       compatible = "qcom,lcc-ipq8064";
> +                       reg = <0x28000000 0x1000>;
> +@@ -685,8 +692,6 @@
> +                       clocks = <&gcc USB30_0_MASTER_CLK>;
> +                       clock-names = "core";
> +
> +-                      syscon-tcsr = <&tcsr 0xb0 1>;
> +-
> +                       ranges;
> +
> +                       status = "disabled";
> +@@ -709,8 +714,6 @@
> +                       clocks = <&gcc USB30_1_MASTER_CLK>;
> +                       clock-names = "core";
> +
> +-                      syscon-tcsr = <&tcsr 0xb0 0>;
> +-
> +                       ranges;
> +
> +                       status = "disabled";
> +diff -Naur a/arch/arm/boot/dts/qcom-ipq8064-r7500.dts b/arch/arm/boot/dts/qcom-ipq8064-r7500.dts
> +--- a/arch/arm/boot/dts/qcom-ipq8064-r7500.dts 2017-02-27 12:35:08.693162274 +0100
> ++++ b/arch/arm/boot/dts/qcom-ipq8064-r7500.dts 2017-02-27 12:35:12.677162395 +0100
> +@@ -131,6 +131,17 @@
> +                       status = "ok";
> +               };
> +
> ++                pinmux at 1a4000b0 {
> ++                        pinctrl-names = "default";
> ++                        pinctrl-0 = <&board_pins>;
> ++
> ++                        board_pins: pinmux_board_pins {
> ++                                pinctrl-single,pins = <
> ++                                        0x00 0x03 /* IPQ_TCSR_USB_CONTROLLER_TYPE_SEL TCSR_USB_SELECT_USB3_DUAL */
> ++                                >;
> ++                        };
> ++                };
> ++
> +               phy at 100f8800 {          /* USB3 port 1 HS phy */
> +                       status = "ok";
> +               };

In my opinion it is a hack/workaround for missing kernel code. The
TCSR isn't related to the pinctrl/pinmux and you are only using
pinctrl-single since it allows you to manipulate the register (or
better any register) you are interested in.

Mathias.